The present invention relates to a refrigerant relief device for a vehicle air conditioner and particularly relates to a refrigerant relief device for a vehicle air conditioner provided with a so-called air conditioning cycle.
In the air conditioning cycle of a vehicle air conditioner, a refrigerant is forcedly fed to a condenser by a compressor. In the condenser, the refrigerant is cooled by the heat exchange between the refrigerant and the external air, and then reaches a liquid tank. In the liquid tank, the refrigerant is subjected to gas-liquid separation, the pressure of the refrigerant is reduced by an expansion valve and the refrigerant is supplied to an evaporator. The evaporator conducts the heat exchange between the supplied refrigerant and the air conditioner blow so as cool the blow. The refrigerant heated by the heat exchange in the evaporator reaches the compressor and is forcedly fed again to make the above-stated cycle.
In recent years, various global or environmental issues arise and attract public attention. In this connection, as for the above-stated air conditioning cycle, the change of types of refrigerants used for air conditioning is demanded for fear of the destruction of the ozone layer or the like. As a new refrigerant, carbon dioxide is proposed.